Description

Traditional data analysis for process optimization deals with data that is recorded before, during or after the process within production. Based on experience and abstracted methods, the components are tested based on tolerances. The behavior during operation is not considered due to high complexity and time-consuming measurement. The laser-based contacting of battery cells allows the components to be operated close to the application. With the help of a battery test system, the battery modules can be discharged and the cell contacting electrically loaded. The use of the operating data opens a new possibility for application-oriented qualification and improvement of the welding process.

At the Fraunhofer ILT, battery modules with seven round cells (type 18650) were produced and operated according to the “Worldwide harmonized light vehicles test cycle” (WLTC). The data set of a module includes:

• Data from the process monitoring system
• Measured values of the contact resistance at the connections after laser processing
• Temperature curve during the operating cycle
• Measured values of the contact resistance after the operating simulation With the help of AI-based evaluation, the data shall improve the weld seam assessment.